It’s well known that living in high-poverty neighborhoods has a significant effect on the mental health of children. Now a new study in the Journal of the American Medical Association offers a nuanced look at what happens after children leave these environments. It highlights a paradox: According to the study authors, led by Harvard professor Ronald Kessler, boys who move into more affluent neighborhoods report higher rates of depression and conduct disorder than their female peers.

Buy why?

The reason for the disparity between boys and girls isn’t exactly pinned down. Kessler points to various factors—community perception, interpersonal skills—as major points of influence: “We had an anthropologist working with us, and the anthropologist went and talked to and watched the kids in the old neighborhoods and the new neighborhoods, and their perception was that when the boys came into the new neighborhood they were coded as these juvenile delinquents,” says Kessler. “Whereas with the girls, it was exactly the opposite. They were embraced by the community—‘you poor little disadvantaged thing, let me help you.’”